Passthrough File Copy

If we want to copy additional files that are not Eleventy templates, we use a feature called Passthrough File Copy to tell Eleventy to copy things to our output folder for us.

Configuration API Method Jump to heading #

Use a configuration API method to specify files or directories for Eleventy to copy.

module.exports = function(eleventyConfig) {
  // Output directory: _site

  // Copy `img/` to `_site/img`
  eleventyConfig.addPassthroughCopy("img");

  // Copy `css/fonts/` to `_site/css/fonts`
  // Keeps the same directory structure.
  eleventyConfig.addPassthroughCopy("css/fonts");

  // Copy any .jpg file to `_site`, via Glob pattern
  // Keeps the same directory structure.
  eleventyConfig.addPassthroughCopy("**/*.jpg");
};

If you do not want to maintain the same directory structure, change the output directory.

How Input Directories are Handled Jump to heading #

As stated above, passthrough file copy paths are relative to the project root and not the input directory. Because of this, if the passthrough file copy path is inside of your input directory, the input directory will be stripped from the output path.

For example:

• input directory is src
• output directory is _site.

If we copy src/img using passthrough file copy, it will copy to _site/img.

module.exports = function(eleventyConfig) {
  // Input directory: src
  // Output directory: _site

  // The following copies to `_site/img`
  eleventyConfig.addPassthroughCopy("src/img");
};

Using Globs Jump to heading #

In this example, we copy all jpg image files to the output folder, maintaining their directory structure. If you do not want to maintain the same directory structure, change the output directory.

Note that this method is slower than non-glob methods, as it searches the entire directory structure and copies each file in Eleventy individually.

module.exports = function(eleventyConfig) {
  // Find and copy any `jpg` files, maintaining directory structure.
  eleventyConfig.addPassthroughCopy("**/*.jpg");
};

With an output directory of _site:

• img/avatar.jpg will copy to _site/img/avatar.jpg
• subdir/img/avatar.jpg will copy to _site/subdir/img/avatar.jpg

Change the Output Directory Jump to heading #

Instead of a string, pass in an object of the following structure: { "input": "target" }.

module.exports = function(eleventyConfig) {
  // Input directory: src
  // Output directory: _site

  // Copy `img/` to `_site/subfolder/img`
  eleventyConfig.addPassthroughCopy({ "img": "subfolder/img" });

  // Copy `src/img/` to `_site/subfolder/img`
  eleventyConfig.addPassthroughCopy({ "src/img": "subfolder/img" });

  // Copy `random-folder/img/` to `_site/subfolder/img`
  eleventyConfig.addPassthroughCopy({ "random-folder/img": "subfolder/img" });
};

Using Globs and Output Directories Jump to heading #

Note that this method is slower than non-glob methods, as it is searching the entire directory structure and copies each file in Eleventy individually.

module.exports = function(eleventyConfig) {
  // Output directory: _site

  // Find and copy any `jpg` files in any folder to _site/img
  // Does not keep the same directory structure.
  eleventyConfig.addPassthroughCopy({ "**/*.jpg": "img" });
};

With an output directory of _site:

• img/avatar.jpg would copy to _site/img/avatar.jpg
• subdir/img/avatar.jpg would copy to _site/img/avatar.jpg

Passthrough by File Extension Jump to heading #

Eleventy, by default, searches for any file in the input directory with a file extension listed in your templateFormats configuration. That means if you’ve listed njk in your templateFormats, we’ll look for any Nunjucks templates (files with the .njk file extension).

If a file format is not recognized by Eleventy as a template file extension, Eleventy will ignore the file. You can modify this behavior by adding supported template formats:

module.exports = function(eleventyConfig) {
  eleventyConfig.setTemplateFormats([
    "md",
    "css" // css is not yet a recognized template extension in Eleventy
  ]);
};

In the above code sample css is not currently a recognized Eleventy template, but Eleventy will search for any *.css files inside of the input directory and copy them to output (keeping directory structure).

You might want to use this for images by adding "jpg", "png", or maybe even "webp".

Emulate Passthrough Copy During --serve Added in v2.0.0 Jump to heading #

The Eleventy Dev Server includes a great build-performance feature that will emulate passthrough file copy.

Practically speaking, this means that (during --serve only!) files are referenced directly and will not be copied to your output folder. Changes to passthrough file copies will not trigger an Eleventy build but will live reload appropriately in the dev server.

You can enable this behavior in your project using this configuration API method:

module.exports = function(eleventyConfig) {
  // the default is "copy"
  eleventyConfig.setServerPassthroughCopyBehavior("passthrough");
};

This behavior will revert to "copy" in your project automatically if:

1. If you are running Eleventy without --serve (a standard build or via --watch)
2. You change from the default development server: Eleventy Dev Server (e.g. swap back to Browsersync)

Advanced Options Added in v2.0.0 Jump to heading #

Additionally, you can pass additional configuration options to the recursive-copy package. This unlocks the use passthrough file copy with symlinks, transforming or renaming copied files. Here are just a few examples:

module.exports = function(eleventyConfig) {
  eleventyConfig.addPassthroughCopy("img", {
    expand: true, // expand symbolic links
  });
};

module.exports = function(eleventyConfig) {
  let copyOptions = {
    debug: true, // log debug information
  };

  eleventyConfig.addPassthroughCopy({ "img": "subfolder/img" }, copyOptions);
};

Review the full list of options on the recursive-copy GitHub repository.

Other pages in Configuration:

• Passthrough File Copy
• Ignore Files
• Filters
  • url
  • slugify
  • log
  • get*CollectionItem
• Shortcodes
• Custom Tags
• Events
• Watch and Serve
  • Eleventy Dev Server
  • Browsersync
  • Vite